But he's not personally liable for a cent of that money.
Obviously, you see the distinction, but it seems clear now that Trump's advisers viewed it less damaging to not release his tax returns than to release them and be forced to launch a slew of counter-attacks to answer for a decade of deals with controversial groups/figures/banks. The obvious risk, which you've exemplified inadvertently in your post, is the conflation of investments of the Trump business empire with Donald's own personal finances. This is probably further complicated by Trump borrowing money from his company at times. Money that could be Russian, Chinese, or Middle Eastern (or perhaps worse ... of the Madoffian/Epsteinien variety). Given the bankruptcies and failed ventures it's probably an absolute mess.
I think though, for whatever reason, many Americans who support Trump simply don't care about his finances. For the same reason they didn't seem to care when it was revealed he hadn't paid income tax in years. Because who here hasn't tried to take an additional iffy write-off? Who here wouldn't have taken a loan for their business from a Chinese bank when they were virtually the only system in the world with substantial capital to lend? There's a sentiment inborn in the American psyche where certain missteps in the pursuit of money are either forgiven or, at least, understood. We draw a line at overt greed it seems - but, for some reason, despite the gilded planes and toilets, Trump doesn't widely seem to be perceived as a greedy individual. Maybe it's because he played the Pied Piper routine for decades with his books and seminars or because of the picture he painted of his family-run enterprise during the campaign. I don't know. Maybe we all see a part of him in ourselves - the desire for fame, greater wealth, power.
In the end I do believe most of the noise being made about Trump's business investments and potential conflicts of interest as it relates to a supposedly mutual national interest is insanely histrionic. It absolutely hurts not to have that information completely public in the traditional sense, but our media doesn't appear to be interested in acting as a truly impartial watchdog anymore, so I'm inclined to again lend my trust to Trump.
Maybe I'll come to regret it, but there's a certain reward in rooting for the underdog.